Cat boat -- issues with such a forward mast?

Discussion in 'Sailboats' started by gmat, Dec 1, 2013.

  1. gmat
    Joined: Nov 2013
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    gmat graham

    I have been looking at a lot of cat boats lately -- mainly cat ketches but also the wyliecat designs.

    I like them a lot, but I have two questions about the very forward mast position that they have:

    a) doesn't having a mast that far forward make the front of the boat quite heavy, and hence possibly wet (digging into waves)?

    b) are your chances of damaging your mast in a collision (with a container for example), higher in a boat with a mast at an extreme forward or aft position? (forward because you probably hit going forward, aft due to whiplash or distance from the point of impact).
     
  2. gonzo
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    gonzo Senior Member

    Cat boats are very full forward. Also, the weight of the mast is not too great in comparison with the total displacement.
    If you hit a partially submerged container with your mast, the location of the mast is the least of your problems
     
  3. PAR
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    PAR Yacht Designer/Builder

    Traditional cat boats are fairly full forward, mostly because of the heft with their typical solid mast in the "eyes", but modern interpretations are finer, using hollow spars. Cat ketches, which I have a bit of experience with, can be finer and often proportionately have the stick a little aft of a cat boat. This is because the mast is relatively smaller and lighter, with the sail area divided up on two poles.

    There are significant hull shape differences between traditional cat boats and modern, looks like a cat boat interpretations. Traditional cat boats are cantankerous beasts, that can be ill handling and often nearly uncontrollable, because of hull shape choices. Most modern "versions" do simple things, like put some air under the aft bilges, so they don't act - well like a cat boat. There are a number of these, seemingly subtle changes to the modern interpretations that make them much better sailers, even if they're not as fast as the holly grail freaks in the golden age.

    Agreed, if you hit a container, the mast will be the least of your worries.
     
  4. SukiSolo
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    SukiSolo Senior Member

    FWIW in smaller cat rigged boats (like racing sailboats) there have been certain trends which aid handling and behaviour. PAR has outlined the hull issues which also include low down hull volume forward to counter nose diving issues. Generally the masts have gone very very slightly further forward but with a lot more rake. This and much better sail design makes them much nicer, well behaved boats.
     
  5. Gary Baigent
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    Gary Baigent Senior Member

    5.5 x 2.25 metre Cox's Bay Skimmer with light wing masts, quite full in bow sections, no ballast, never had any burying, broaching problems. The drawings are of a proposed 6.5 metre version, that could be single or double rigged - but probably the latter.
     

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  6. SukiSolo
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    SukiSolo Senior Member

    That looks very sweet Gary. She's floating quite nicely. If she were mine I'd be tempted to have a (tiny) little more freeboard but that may be personal and me being used to some very choppy UK water especially off the south coast.

    How many crew are intended or is it just a solo jobbie?
     

  7. Gary Baigent
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    Gary Baigent Senior Member

    Sukisolo, have sailed with total of three aboard but usually with two; also with the foresail double reefed, full mainsail, can solo the boat in quite decent breezes - but you have to play the main sheet fairly continuously.
    However in lighter conditions, full sail on both masts and sailing solo, the boat is definitely good fun but requires attention, especially in gusts.
    Sail area total is 22m2, boat weighs around 120 kgs.
    But the skimmer is at its best with two, carrying full sail on both masts, crew stacked out on the wide decks giving plenty of power and righting moments.
    Freeboard seems okay to us - and we sail often in wind against tide conditions here, but yes, can be wet in larger waves.
     

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